diff --git a/lib/conn/conn.go b/lib/conn/conn.go
index cf29acb3..4e511d19 100755
--- a/lib/conn/conn.go
+++ b/lib/conn/conn.go
@@ -14,6 +14,7 @@ import (
 	"net/url"
 	"strconv"
 	"strings"
+	"sync"
 	"time"
 
 	"ehang.io/nps/lib/common"
@@ -371,7 +372,10 @@ func CopyWaitGroup(conn1, conn2 net.Conn, crypt bool, snappy bool, rate *rate.Ra
 	//if flow != nil {
 	//	flow.Add(in, out)
 	//}
-	err := goroutine.CopyConnsPool.Invoke(goroutine.NewConns(connHandle, conn2, flow))
+	wg := new(sync.WaitGroup)
+	wg.Add(1)
+	err := goroutine.CopyConnsPool.Invoke(goroutine.NewConns(connHandle, conn2, flow, wg))
+	wg.Wait()
 	if err != nil {
 		logs.Error(err)
 	}
diff --git a/lib/goroutine/pool.go b/lib/goroutine/pool.go
index ca91d6d5..60717e68 100644
--- a/lib/goroutine/pool.go
+++ b/lib/goroutine/pool.go
@@ -44,13 +44,15 @@ type Conns struct {
 	conn1 io.ReadWriteCloser // mux connection
 	conn2 net.Conn           // outside connection
 	flow  *file.Flow
+	wg    *sync.WaitGroup
 }
 
-func NewConns(c1 io.ReadWriteCloser, c2 net.Conn, flow *file.Flow) Conns {
+func NewConns(c1 io.ReadWriteCloser, c2 net.Conn, flow *file.Flow, wg *sync.WaitGroup) Conns {
 	return Conns{
 		conn1: c1,
 		conn2: c2,
 		flow:  flow,
+		wg:    wg,
 	}
 }
 
@@ -67,6 +69,7 @@ func copyConns(group interface{}) {
 	if conns.flow != nil {
 		conns.flow.Add(in, out)
 	}
+	conns.wg.Done()
 }
 
 var connCopyPool, _ = ants.NewPoolWithFunc(200000, copyConnGroup, ants.WithNonblocking(false))